Final answer:
The term 'the genomic RNA can function as mRNA' is related to the process of reverse transcription, where viral RNA is converted into DNA by the enzyme reverse transcriptase.
The correct answer to the question is option (d) Reverse transcription.
Step-by-step explanation:
The phrase 'the genomic RNA can function as mRNA' refers to the process by which some RNA viruses can directly use their RNA as messenger RNA (mRNA) inside a host cell. This is facilitated by an enzyme these viruses carry known as reverse transcriptase. The correct option is (d) Reverse transcription. Reverse transcription is the process where the viral RNA genome is reverse-transcribed by reverse transcriptase into complementary DNA (cDNA), which can then be integrated into the host DNA and transcribed to produce viral RNA. This RNA can then be used as mRNA for protein synthesis or as genomic RNA for new virus particles.
It's important to note that reverse transcriptase actually transcribes RNA back to DNA, not DNA to RNA as mentioned in the question. Transcription is the regular cellular process in which DNA acts as a template for synthesizing RNA. Therefore, reverse transcription is considered the reverse of this normal transcription process, allowing RNA to serve as a template for DNA synthesis.